The effects of beta blockers on the heart include a reduction in heart rate and an improvement in heart function over time. A doctor can prescribe these medications to a patient with a heart condition or a medical issue that puts stress on the heart. Some patients take beta blockers for anxiety and extreme stress, for instance, to protect their hearts and allow them to resume normal activities. Because the effects of beta blockers on the heart can be cumulative, it is important to take the medications consistently and to stop taking them only under medical supervision, rather than quitting cold.
These medications act on the beta-adrenergic receptors found in the heart muscle. They occupy the receptors so chemicals like adrenaline cannot stimulate them. When the body produces a flood of adrenaline due to stress, exercise, or a medical condition, the medication will prevent the hormone from triggering a cascade of reactions in the heart. The precise effects of beta blockers on the heart can vary depending on the class of medication, as some are more selective about the receptors they block.
When patients take beta blockers, their hearts will beat more slowly and steadily. Sometimes patients actually develop bradycardia, a dangerously low heart rate. They need treatment with beta blockers known to offset bradycardia while still preventing a fast heart rate, called tachycardia. The effects of beta blockers on the heart can include a drop in the production of harmful compounds the heart normally makes under stress, as in patients with chronic heart failure. This can prevent complications and reduce the risk of death.
Patients who exert themselves with exercise and stressful activities may notice that the effects of beta blockers on the heart include maintenance of a low heart rate even under stress. It can be challenging to reach a target heart rate in cardiac exercise. Such patients should talk to their doctors about adjusting the target heart rate to find a zone beta blockers will allow them to reach. This slowing effect can also help patients who experience extreme anxiety, as their hearts will not start to race when they are in tense situations.
In the long term, the heart will not have to work as hard, and it can grow stronger and less prone to complications. The patient may also find that use of beta blockers dilates the blood vessels and lowers blood pressure. A doctor will usually recommend periodic follow-up appointments to see how well the patient responds to the medication and make dosage adjustments if necessary.